考虑摩擦系数的沥青路面动态轴载换算

Conversion of Dynamic Axle Load on Asphalt Pavement Considering Friction Coefficient

为研究复杂工况下的动态轴载换算,分析了车辆移动荷载作用下沥青路面的动力响应,对数值计算的有效性和车辆行驶特性的影响进行了研究,并提出了动态轴载换算公式.基于二维Lamb问题验证了数值计算的有效性,并建立刚性基层沥青路面的三维动力学数值模型,分析不同车速、路面摩擦系数和轴载等因素的影响.当荷载匀速移动时,轴载和路面摩擦系数对路面动力响应的影响明显,考虑摩擦系数的动态轴载换算指数明显大于静态荷载.结合车辆和路面多种影响因素的三维有限元计算模型更符合沥青路面结构的实际受力状态,动态轴载换算公式可用来改进当前的规范设计.

In order to investigate the dynamic axle load conversion in complex conditions, the dynamic response of as- phalt pavement subjected to moving load is analyzed, the validity of the numerical calculation and the influence of vehi- cle characteristics are discussed, and a conversion formula of the dynamic axle load is set up. Then, based on the two- dimension Lamb problem, the effectiveness of the numerical calculation is verified, and a three-dimension dynamic nu- merical model of asphalt pavement with rigid base is established to analyze the effects of vehicle speed, road surface fric- tion coefficient and axle load. The results show that, when the vehicle moves at a constant speed, both the axle load and the road surface friction coeffcient remarkably influence the dynamic response of pavement; and that the conversion co- efffcient of the dynamic axle load considering the friction coefficient is significantly greater than that of the static axle load. Moreover, it is found that the three-dimension finite element model, which takes into consideration various affec- ting factors of the vehicle and the asphalt pavement, accords well with the actual stress state of asphalt pavement struc-ture; and that the presented conversion formula is feasible in improving the current design specifications.